Dr. Ronald D. Berger

Dr. David Douglass Spragg is a Professor of Medicine in the Department of Medicine (Division of Cardiology) at Johns Hopkins. In addition, he is the inaugural Edward St. John Professor of Cardiology. His research focuses on treatments for atrial fibrillation (AF), and particularly on catheter ablation for AF. Dr. Spragg received his undergraduate degree in the Comparative Study of Religion from Harvard College. He earned his medical degree from the College of Physicians and Surgeons at Columbia University. After pursuing a Sarnoff Cardiovascular research fellowship at Brigham and Women's Hospital, Dr. Spragg completed his internship and residency at Massachusetts General Hospital. He came to Johns Hopkins in 2001 for Cardiology and Cardiac EP fellowships. He served as chief fellow for the Cardiology program, and was recognized for his research during fellowship as the Michel Mirowski Cardiology Fellow. Dr. Spragg joined the faculty as an Assistant Professor in 2006, and was promoted to Associate Professor in 2014. He was promoted to the rank of Professor of Medicine in 2024. Besides his teaching and clinical appointments at the Johns Hopkins School of Medicine, Dr. Spragg is the Director of the Johns Hopkins Atrial Fibrillation Research Program. He is a Fellow of the Heart Rhythm Society. Dr. Spragg is rated as a Distinguished provider by MediFind in the treatment of Atrial Fibrillation. His top areas of expertise are Atrial Fibrillation, Arrhythmias, Cardiac Tamponade, Cardiac Ablation, and Pacemaker Implantation.

Joseph Marine, MD, MBA, FACC, FHRS, is a clinical cardiac electrophysiologist who practices primarily at the Johns Hopkins Hospital in Baltimore, Maryland. He is a Professor of Medicine at the Johns Hopkins University School of Medicine and holds appointments as Vice-Director of Operations for the Division of Cardiology and Section Chief of Cardiology for Johns Hopkins Community Physicians. He trained at UC San Francisco Medical School, Brigham and Women’s Hospital/Harvard Medical School, Boston University Medical Center, and Beth Israel Deaconess Medical Center. Dr. Marine has lectured widely on a variety of arrhythmia topics and has served as a co-director of the American College of Cardiology (ACC) Cardiovascular Overview and Board Review Course for 10 years. He currently serves on the ACC Board of Governors and is co-editor of the ACC/HRS EP Self-Assessment Program. He also serves on other committees for the ACC, the Heart Rhythm Society, and MedChi. He is co-author of more than 130 original research and review articles and has served on writing committees for several national cardiology practice and training guidelines. As a clinical cardiac electrophysiologist, Dr. Marine specializes in the diagnosis and treatment of arrhythmias, which are heart rhythm disorders that cause the heart to beat too rapidly, too slowly, or irregularly. His research focuses on further improving the safety and effectiveness of catheter ablation and other treatments for atrial fibrillation and other atrial and ventricular arrhythmias. Dr. Marine is rated as a Distinguished provider by MediFind in the treatment of Atrial Fibrillation. His top areas of expertise are Atrial Fibrillation, Atrioventricular Nodal Reentrant Tachycardia (AVNRT), Arrhythmias, Cardiac Ablation, and Heart Transplant.

Jonathan Chrispin, M.D., is an Associate Professor of Medicine in the Johns Hopkins Medicine Division of Cardiology, Electrophysiology and Arrhythmia, as well as an Associate Professor of Biomedical Engineering at Johns Hopkins University. Dr. Chrispin focuses on all aspects of clinical electrophysiology, including pacemaker/defibrillator implantation and complex catheter ablation for atrial and ventricular arrhythmias. Dr. Chrispin received his Bachelor of Arts degree from Harvard University. He received his Doctor of Medicine degree from Vanderbilt University. He completed intern and residency training in internal medicine at The Johns Hopkins Hospital, where he also completed a fellowship in cardiovascular disease and served as chief clinical cardiac electrophysiology fellow. He is a member of the American College of Cardiology, the American Heart Association, and the Heart Rhythm Society. Dr. Chrispin directs the Ventricular Arrhythmia Ablation and Research program, focusing on using advanced cardiac imaging to better understand the structural substrate associated with the development of ventricular arrhythmias and using artificial intelligence to improve the risk stratification of sudden cardiac death. Further, he is involved in developing clinical trials to improve the safety and efficacy of catheter ablation for the treatment of ventricular tachycardia. His work has led to Dr. Chrispin publishing in a number of international journals, including Circulation, the Journal of the American College of Cardiology, Heart Rhythm Journal, Nature Cardiovascular Research, Journal of the American Heart Association, and EP Europace. Dr. Chrispin is rated as an Elite provider by MediFind in the treatment of Atrial Fibrillation. His top areas of expertise are Ventricular Tachycardia, Arrhythmias, Sarcoidosis, Cardiac Ablation, and Pacemaker Implantation.